Free flowing materials, such as grain, chemicals, and cement, among many others, are commonly dispensed into piles or containers for transportation, use, and/or storage. It is often inefficient and/or hazardous to use human labor to monitor the dispensing process to determine when to restrict or otherwise modify the flow. For example, chemical transport containers are often opaque, requiring a person to monitor the container capacity at close range, increasing the risk for exposure to hazardous materials. Thus, attempts have been made to monitor the dispensing process using mechanical methods, such as tilt-sensing devices.
Current tilt-sensing devices are problematic. For example, devices incorporating mercury switches are inherently dangerous due to the presence of mercury, limiting their application. Similarly, devices incorporating limit switches acted on by the weight of a ball contained within the device are inadequate as, in practice, the ball does not consistently trigger the switch as designed. These devices are prone to failure due to contamination and excess wear of certain components, such as the transmitting wires. Because these devices are largely self-contained and rigidly assembled, users are unable to disassemble the devices to attempt to repair them. Thus, a need exists for a reliable, repairable tilt-sensing device that is resistant to contamination and capable of automatically sensing the height of a free flowing material being dispensed and communicating when the material has reached a particular height.